· By Buffy
What Counts as a Complication
Anything that isn't just hours, minutes, and seconds — a taxonomy of watch complications and the one insight that explains almost all of them.
In horology a complication is any function beyond simple hours, minutes, and (usually) seconds. The word is a translation of the French complication — and the honest truth is that most complications are variations on a single idea: count something else cleverly.
The taxonomy
Counting elapsed time (the stopwatch family):
- Chronograph — seconds, minutes, sometimes hours, on demand.
- Flyback, rattrapante (split-seconds) — counting tricks on top of counting.
Counting calendar time (the computer family):
- Date, day, month — wheels and pins.
- Perpetual calendar — remembers leap years with a 4-year cam.
- Moonphase — a 59-tooth (or better) simulation of the lunar month.
- Annual calendar — the honest middle: knows 30 vs 31, asks for help in March.
Counting sounds (the music family):
- Minute repeater — strikes hours, quarters, minutes.
- Grande/petite sonnerie — striking on autopilot; alarm — striking on purpose.
Fighting position errors (the physics family):
- Tourbillon — rotates the escapement to average gravity.
- GMT / world time — counts a second (and third) time zone.
Counting the spring’s mood:
- Power reserve — shows how much counting is left.
The insight
Each complication is a mechanical memory plus a display. The perpetual calendar’s memory is a 48-month cam; the chronograph’s is its coupling lever; the repeater’s is a rack-and-snail that physically measures how far the minute hand has passed. There is no software, no sensor — only geometry that remembers. When you press a pusher and a tiny lever falls into a notch, that notch is the data structure.
What makes one good
Watchmakers judge complications by: thinness of the added module, robustness of the memory (what happens if you set it backwards?), service burden (how many extra springs fly away at disassembly), and whether the complication earns its friction budget. The pages in this section score each candidate on those terms — including the parts of the story the marketing omits.